Rack Ruler
Math-free measuring
This tool has an admittedly narrow application, but I’ve found it quite useful for working in a datacenter. It’s a ruler that’s scaled to count spaces in a computer or audio rack, which measure a standard 1.75 inches, making quick work of documenting racks or figuring out if there is enough space in an existing install.
01/14/10Middle Atlantic 8 ft. Rack Ruler $17